﻿using System.Windows.Data;
using System;

namespace SessionHunter.Converters
{
    /// <summary>
    /// Converts a boolean binding to the opposite value
    /// </summary>
    /// <remarks>http://www.codeproject.com/Articles/24330/WPF-Bind-to-Opposite-Boolean-Value-Using-a-Convert</remarks>
    public class BoolToOppositeBoolConverter : IValueConverter
    {
        #region IValueConverter Members

        /// <summary>
        /// Converts a value to the opposite boolean value.
        /// </summary>
        /// <param name="value">The value produced by the binding source.</param>
        /// <param name="targetType">The type of the binding target property.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        public object Convert(object value, Type targetType, object parameter,
            System.Globalization.CultureInfo culture)
        {
            if (targetType != typeof(bool))
                throw new InvalidOperationException("The target must be a boolean");

            return !(bool)value;
        }

        /// <summary>
        /// Converts a value to the opposite boolean value.
        /// </summary>
        /// <param name="value">The value that is produced by the binding target.</param>
        /// <param name="targetType">The type to convert to.</param>
        /// <param name="parameter">The converter parameter to use.</param>
        /// <param name="culture">The culture to use in the converter.</param>
        /// <returns>
        /// A converted value. If the method returns null, the valid null value is used.
        /// </returns>
        public object ConvertBack(object value, Type targetType, object parameter,
            System.Globalization.CultureInfo culture)
        {
            throw new NotSupportedException();
        }

        #endregion
    }
}